Waste RO water

Down the drain.

I always think I should do something else with it(Like store it for watering outdoor plants or something), but I never do.
 
mine goes to my sump pump which has been rerouted and dumps into my folwer garden evertime it turns on

saves me some watering in the summer
 
<a href=showthread.php?s=&postid=6845125#post6845125 target=_blank>Originally posted</a> by jh2pizza
we could bottle it and sell it on ebay to the folks who live in dry places.:)
Click to expand...

I think you are on to something. put a fancy label on it and everyone will buy it....

EVIAN......NAIVE coinsidence I think not:)
 
I use mine on my FW planted tanks. Works like a charm.

I'm getting a new RO unit today from Buckeye Field Supplies that will give me more water so I'm just wondering what to do with the excess. I like the washing machine idea.
 
<a href=showthread.php?s=&postid=6845908#post6845908 target=_blank>Originally posted</a> by reiverix
I use mine on my FW planted tanks. Works like a charm.

I'm getting a new RO unit today from Buckeye Field Supplies that will give me more water so I'm just wondering what to do with the excess. I like the washing machine idea.
Click to expand...

what do you mean give you more water?

is it a higher rated per day membrane? if so, unless you "make" more water you should hav either the same or less waste water assuming you have upgraded.
 
I would like to put a small garden pond outside, and run the line to that..............but I'll probably never get around to doing it.
 
what do you mean give you more water?

is it a higher rated per day membrane? if so, unless you "make" more water you should hav either the same or less waste water assuming you have upgraded.
Click to expand...
Well yeah I'm going from a 20gpd to a 75gpd. But I see what you mean. No need to run it all the time.
 
Down the drain, but instead of getting 4:1 ratio I am getting like 0.6:1 since I am using a Permeate Pump which sends about 85% of the waste water that would normally end up going down the drain back through the membrane to be filtered againââ"šÂ¬Ã‚¦
 
<a href=showthread.php?s=&postid=6849646#post6849646 target=_blank>Originally posted</a> by Sloth
That will probably reduce the life of your membranes.
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I wouldn't say that your membrane would be reduced in life... Letââ"šÂ¬Ã¢"žÂ¢s say that a TDS of 150ppm on a membrane would give you 2000gal of RO production... The Permeate Pump is inline between the filters and the membrane... So the water that is being recycled has already gone through the first 4 filters (Sediment, Carbon, and 2x DI) and when the pump sends it back through for another pass on the membrane so it would be no different then just sending that 4gal worth of water down the drain and taking on the next 5gal of water... does that make since ??
 
Let me try to break it down some more...

From the house you have a TDS reading of 150ppm...

Goes through the Sediment filter and then has a TDS reading of 125ppm

Goes through Carbon filter and then has a TDS reading of 100ppm

Goes through the first DI (Deionization) filter and then has a TDS reading of 75ppm

Goes through the second DI (Deionization) filter and then has a TDS reading of 50ppm

Passes though the Permeate Pump to the 100gpd membrane where you would get 4gal of waste to 1gal of RO...

Waste would have a TDS reading of 50ppm where the 1gal that passed through the membrane would have a very low to 0ppm reading...

Most of that waste water that has a TDS reading of 50ppm is then passed back through the membrane again...


NOTE: The numbers used above were just for referenceââ"šÂ¬Ã‚¦.
 
<a href=showthread.php?s=&postid=6850049#post6850049 target=_blank>Originally posted</a> by asnatlas
Most of that waste water that has a TDS reading of 50ppm is then passed back through the membrane again...
Click to expand...
I'm a little confused about where the pump is getting water and where it's sending it. I think you're saying it's taking the membrane waste and putting it back through the membrane for another pass.

And you're saying that it won't shorten the membrane life because the membrane waste has the same concentration of TDS as the water coming from the last DI cartridge anyway. (50ppm)

BUT

It's not 50 ppm. It's more. When the water went through the membrane 4 gallons came out as waste and one gallon came out as pure water (0 ppm).

50 parts TDS per 1,000,000 parts water went in.
The membrane took away 1/4 of the water (250,000 parts).
Now its 50 parts TDS per 750,000 parts water coming out as waste.

50 parts per 750,000 = 62.5 parts per million.

So every time the pump sends waste water through the membrane again, the membrane takes out more and more pure water. So the waste water (containing all the junk that didn't pass through the membrane) gets more and more concentrated with TDS. Which cruds up the membrane faster.

well, I THINK I'm right :confused: If I'm wrong, don't tell me :D

edit: and burning through membranes faster isn't necessarily a bad thing. If it's more cost effective to buy membranes more often and have a lower water bill, then its a good idea.

I saw that link about the pump though. Says it's powered by brine in the waste water and requires no electricity. Sounds too good to be true.:strooper:
 
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I agree that the DI should be after the RO membrane

I'd have to agree with Sloth on this one from what I have read the permeate pump's function is to balance out the back pressure caused by a pressure storage tank. Which in that application makes sense.
 
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